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double de-cat


drift_bear
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im wanting to go double de-cat with my TT, i have got a pair of de-cats coming along with a restrictor ring aswell, will i need anything else to put on aswell or can i just put on the double de-cat and ring and drive? i will be saving up the money and parts to go full BPU by the summer.

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its still running stock boost and will be untill i go full bpu

 

You won't be running stock boost though bud, you will be running whatever the restriction ring is bored out to make. If it is a 1.2bar restriction ring you will be running around 1-1.2bar depending on the exhaust, intake etc.

 

You will want all new gaskets, one from the tubby to the 1st decat, 2 for between the 1st decat and the 2nd decat (as the RR is easily sandwiched here) and 1 for between the 2nd decat and the exhaust. A little bit of exhaust gasket sealant will go well too. 1 tube will do the job nicely. You also want to get some nice shiney new nuts and bolts to fit everything together. I would guess that the ones coming from the hotside of the turbo will have seen better days so you will need 3 nuts there, you will need another 4 nuts and 4 bolts for the rest of the decat joins.

 

If you don't want to remove the fuel cut then I would suggest leaving everything as it is until you want to go down that route.

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ok then, ill just collect everything and get all done at once. is it easy to do BPU yourself or is it best to goto a garage? are there any garages up here that do it?

 

Depends on how handy you are with a spanner :D

 

The exhaust is an absolute canter. The only hard part is getting the 1st cat nuts off without shearing any studs. Get a hold of a gas bottle, some plusgas and a good set of spanners/ratchet/sockets and it should go OK.

 

The FCD is a few wires. There are many guides on how to fit it so as long as you are confident with a soldering iron it is a very straight forward job. If you can, get an FCD and a de-limiter (I think you can get these in one?). That way your car won't be restricted to 112mph if it currently is.

 

I've never fitted a boost controller so I am uncertain of how easy it is. I can't see it being that difficult. I would imagine you only need to feed +ive, -ive and possibly a switched +ive to the controller, the controller will then plug into the solenoid. Plumbing the solenoid is easy enough.

 

How much further are you going? Intercooler? Induction kits?

 

All reasonably straight forward if you are confident with that kind of work :)

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Exactly, which means supporting mods would be required which is basically what BPU is anyway.

 

My advise is save your money, get all the parts required together and then fit them.

 

Job done.

 

Ahh. You didn't use the "Quote" button previously so I assumed you were referring to what I had wrote above your post.

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An FCD would just about cover it.

 

To fit the intercooler the front bumper has to be removed. Straight forward enough but there are a LOT of clips if it is stock. The induction kit is a piece of pie as is the boost gauge.

 

It's one of those things, if you decide to put it into a garage it is a LOT of hours work to fit all that stuff. It isn't hard work, it is just time consuming.

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I've noted that at BPU levels in my 95RZ, using a RR with the stock air box (uprated panel filter) gives me 1.0 bar on WOT, running a RR with an induction kit gives me 1.2 bar on WOT, just thought I'd mention it. I havent really noticed a difference between 1.0 and 1.2 bar on WOT.

 

You'll also want to run some colder plugs suitable for BPU levels.

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Can I ask what actual the purpose of a boost controller is?

 

From what I've gleaned in passing its used to increase the boost produced (not to limit it) but surely a decat is doing the same and the restrictor ring is used to keep it in check so the turbos don't spin to destruction.

 

I guess what I'm trying to ask is whether a boost controller is necessary for going BPU if a decat and RR is used?

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AFIAK a RR will increase the boost levels to a certain limit (ie: 1.2 bar) but it wont control them, a boost controller will regulate the boost to give you a more consistent boost level at WOT.

 

I have a boost controller fit to mine (was already on the car when I purchased it) however I dont have it on as it doesnt have a digital display to indicate what boost it is set to.

 

Edit:

http://www.torquecars.com/tuning/boost-controllers.php

Edited by Angarak (see edit history)
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I would always recommend aiming for around 1.0bar with the rr and then up that to 1.2 with a boost controller. As mentioned a boost controller will hold it rock steady. Without one you will run the risk of overboosting in higher gears if hitting 1.2 in lower gears, or having to live with lower boost in lower gears to combat this.

 

 

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AFIAK a RR will increase the boost levels to a certain limit (ie: 1.2 bar) but it wont control them, a boost controller will regulate the boost to give you a more consistent boost level at WOT.

 

I have a boost controller fit to mine (was already on the car when I purchased it) however I dont have it on as it doesnt have a digital display to indicate what boost it is set to.

 

Edit:

http://www.torquecars.com/tuning/boost-controllers.php

 

a boost controller is nessessary on the uk spec to increase the boost, as decats alone dont do this due to them having bigger wastegates, there not required on a jspec, 2 decats and rr is all that needed to increase the boost

 

I would always recommend aiming for around 1.0bar with the rr and then up that to 1.2 with a boost controller. As mentioned a boost controller will hold it rock steady. Without one you will run the risk of overboosting in higher gears if hitting 1.2 in lower gears, or having to live with lower boost in lower gears to combat this.

 

/QUOTE]

 

Thanks chaps.

 

More feckin' gadgets needed so. :(

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so far i have the following

 

blitz FMIC

blitz induction kit

greddy profac B boost controller

blitz boost guage

 

got double de-cat and RR coming anyday now aswell, also the car is de-limited anyway

 

so all i need to get still are :

 

walbro fuel pump

colder plugs

fcd

 

or am i forgetting stuff?

 

I'd also fit a Exhaust Gas Temp gauge or Air/Fuel Ratio gauge to be on the safe side.

 

If it's not been changed recently I would also fit a new fuel filter.

 

When you come to change the plugs you may find the coil pack connectors are in a bad way - they become brittle and break due to the engine heat over time - upping the boost will highlight any poor connection. They are cheap so worth fitting new ones at the same time.

 

I'd also buy 2 new cam cover breather pipes whilst you're at it, as you'll probably find the ones fitted are hard and brittle when changing the plugs.

Edited by Nic (see edit history)
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I would always recommend aiming for around 1.0bar with the rr and then up that to 1.2 with a boost controller. As mentioned a boost controller will hold it rock steady. Without one you will run the risk of overboosting in higher gears if hitting 1.2 in lower gears, or having to live with lower boost in lower gears to combat this.

 

Agree.

 

A boost controller with 'gain' feature can also noticeably reduce the spool up time of the turbos.

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I'd also fit a Exhaust Gas Temp gauge or Air/Fuel Ratio gauge to be on the safe side.

 

If it's not been changed recently I would also fit a new fuel filter.

 

When you come to change the plugs you may find the coil pack connectors are in a bad way - they become brittle and break due to the engine heat over time - upping the boost will highlight any poor connection. They are cheap so worth fitting new ones at the same time.

 

I'd also buy a 2 new cam cover breather pipes whilst you're at it, as you'll probably find the ones fitted are hard and brittle when changing the plugs.

 

Exactly this happened to mine the day I upped the boost, started missing and spluttering on anything over stock boost. I 'retensioned' the spring fingers inside the connectors for now until I get round to replacing the crumbled plastic connector housing and since summer it has been ok so far. On the subject of boost control, I have used a simple manual boost controller and tbh it works but is a pants way of doing it. The one I used has a very coarse adjustment and really you need a EBC which monitors and adjusts the boost according to whats dialled in. Mine is very temperature dependant and I need to get a ebc asap.

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I was just about to post a question about manual boost controllers Shane but unfortunately you've provided the answer I really didn't want to hear!

 

Are ALL manual controllers as bad as each other. They really have my attention at the moment. They can be picked up for pennies compared to the electronic units, are so much simpler to fit and to be quite honest I already have a drawer full of guages and gizmos to fit, I'd really like to save myself the pain of fitting and probably refitting even more circuitry to this project.

 

I have a decent boost guage to fit to keep a check on what the turbos are doing, apart from the minute alterations that an electronic controller can provide is there really much of a disadvantage to fitting a suitable manual version?

 

Truth be told I'm just a cheapskate!

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